# East-West Schism (1054)

URL: https://christianity-history.com/timeline/1054-east-west-schism
Location: Constantinople
Themes: Schism

Papal legates excommunicate Patriarch Michael Cerularius, marking the break between Catholic and Orthodox churches. At this point in the timeline (16 July 1054), the Bishop of Rome was Pope Leo IX (12 February 1049 – 19 April 1054).

## Why it matters
The schism remains the largest division in Christianity.

Pope at the time: [Pope Leo IX](https://christianity-history.com/popes/pope-leo-ix)

## Sources
- [Wikipedia — East–West Schism](https://en.wikipedia.org/wiki/East%E2%80%93West_Schism)
- [Encyclopaedia Britannica topic lookup — East-West Schism](https://www.britannica.com/search?query=East-West+Schism)
- [Wikipedia — Medieval Church (period overview)](https://en.wikipedia.org/wiki/History_of_the_Catholic_Church#Middle_Ages)